Windows WebKitLegacy is the last frontend that does not have automatic generation of keys and bridging to WebCore::Settings/WebCore::RuntimeEnabledFeatures. This means that whenever a new preference flag is added that someone wants to use from tests, they either have to explicitly exclude the test from Windows or add a bunch of boiler plate. We should match Cocoa WebKitLegacy and WebKit by generating these from the yaml files in WTF.
<rdar://problem/75396061>